Notes

7. Sir John de Montgomery, living c.1190 = Helen, dau. of Robert
of Kent. [ES III/4: 640]

B. Sir John de Montgomery of Eastwood, 4th of Eaglesham (d
c1214) m. Helen de Kent (dau of Robert de Kent of Innerwick)

Sources disagree on the generations around here. We follow "The
Origin and History of the Montgomeries" but TSP does not agree
down to Alexander (and then disputes that his wife was a
daughter of the 1st Earl of Douglas). The uncertainty is such
that BP1934 (Eglinton and Winton) does not record any details
for the ancestry of Sir John de Montgomery of Eaglesham (who
died in 1401 having distinguished himself at the battle of
Otterburn in 1388). From him onwards there appears to be general
agreement.